The chief goal of this project is the comparison of the urinary excretion of epinephrine, nor-epinephrine, dopamine, homovanillic acid, and plasma dopamine - beta-hydroxylase in immunologic and non- immunologic asthma. Since previous studies have demonstrated high urinary dopamine excretion in certain asthmatic patients, this investigation is designed to ascertain whether this phenomenon simply reflects excessive stress in these patients or whether it may indicate an arrest at the dopamine level in a normal metabolic pathway of catecholamine synthesis. Catecholamine urinary excretion and plasma dopamine-beta -hydroxylase will be studied in both immunologic and non- immunologic asthma under controlled hospital conditions. Comparisons will be made in both groups of patients before and after standardized exercise tests, bronchial challenges with histamines, specific allergens or bacterial filtrates. Since ablation of the pituitary gland in animals causes a reduction of catecholamine biosynthetic enzymes, the kinetics of dopamine excretion will also be studied in asthmatic patients whose steroid metabolism is impaired because of their therapeutic requirements for exogenous steroids.